feat: animate hit or miss message instead of snackbar

lib/level.dart

@@ -1,5 +1,4 @@
 import 'dart:async';
-import 'dart:io';
 
 import 'package:flutter/material.dart';
 import 'package:audioplayers/audioplayers.dart';
@@ -23,7 +22,7 @@ class InputDirection {
   bool right = false;
 }
 
-class _LevelState extends State<Level> {
+class _LevelState extends State<Level> with SingleTickerProviderStateMixin {
   final player = AudioPlayer();
   bool _isPlaying = true;
   Duration? _duration;
@@ -35,8 +34,13 @@ class _LevelState extends State<Level> {
   final FocusNode _focusNode = FocusNode();
   InputDirection inputDirection = InputDirection();
 
+  String hitOrMissMessage = 'Play!';
+
   List<Note> notes = [];
 
+  late AnimationController _animationController;
+  late Animation<double> _animation;
+
   @override
   void setState(VoidCallback fn) {
     // Subscriptions only can be closed asynchronously,
@@ -49,6 +53,15 @@ class _LevelState extends State<Level> {
   @override
   void initState() {
     super.initState();
+
+    _animationController = AnimationController(
+      vsync: this,
+      duration: Duration(seconds: 2),
+    );
+    _animation =
+        Tween<double>(begin: 1.0, end: 0.0).animate(_animationController);
+    _animationController.forward();
+
     // Use initial values from player
     player.getDuration().then(
           (value) => setState(() {
@@ -109,23 +122,20 @@ class _LevelState extends State<Level> {
           if (keypressCorrect) {
             print("you hit!");
             note.wasHit = true;
-
-            ScaffoldMessenger.of(context).showSnackBar(
-              SnackBar(
-                content: Text('Great!'),
-                duration: Duration(milliseconds: 500),
-              ),
-            );
+            _animationController.reset();
+            _animationController.forward();
+            setState(() {
+              hitOrMissMessage = 'Great!';
+            });
           }
         } else if (note.position < -0.5 * 1.0 / 60.0) {
           print("Missed");
           note.wasHit = false;
-          ScaffoldMessenger.of(context).showSnackBar(
-            SnackBar(
-              content: Text('Missed!'),
-              duration: Duration(milliseconds: 500),
-            ),
-          );
+          _animationController.reset();
+          _animationController.forward();
+          setState(() {
+            hitOrMissMessage = 'Missed';
+          });
         }
       }
     });
@@ -215,12 +225,15 @@ class _LevelState extends State<Level> {
               top: 50,
               width: MediaQuery.of(context).size.width,
               left: 0,
+              child: FadeTransition(
+                opacity: _animation,
                 child: Text(
-                "Great!",
+                  hitOrMissMessage,
                   textScaler: TextScaler.linear(4),
                   textAlign: TextAlign.center,
                 ),
               ),
+            ),
             Positioned(
               left: MediaQuery.of(context).size.width / 2 - 50,
               bottom: 50,
@@ -238,6 +251,7 @@ class _LevelState extends State<Level> {
 
   @override
   void dispose() {
+    _animationController.dispose();
     _durationSubscription?.cancel();
     _positionSubscription?.cancel();
     player.dispose();